Electrical connector having a housing and an electrical contact and electrical contact

ABSTRACT

An electrical contact ( 1 ) is shown having a conductor connection region ( 2 ) for connection to an electrical conductor wire and a contact-making region ( 3 ) for making contact with a complementary contact pin is specified, the contact-making region essentially being designed in the form of a box with two side walls ( 4, 5 ), a top wall ( 6 ) and a bottom wall ( 7 ), the bottom wall ( 7 ) and the top wall  (6 ) having a different width in the direction perpendicular to the plug-in direction, in such a way that the side walls ( 4, 5 ) run in a manner inclined with respect to the bottom and top walls ( 6, 7 ) and with respect to one another.

The invention relates to an electrical connector having a housing andhaving at least one electrical contact, the housing having at least onechamber for the electrical contact and the electrical contact having aconductor connection region for connection to an electrical conductorwire and a contact-making region for making contact with a complementarycontact pin, the contact-making region essentially being designed in theform of a box with two side walls, a top wall and a bottom wall, the topand bottom wall having a different width in the direction perpendicularto the plug-in direction, in such a way, that the side walls run in amanner inclined with respect to the bottom and top walls and withrespect to one another.

Furthermore, the invention relates to an electrical contact having aconductor connection region for connection to an electrical conductorwire and having a contact-making region for making contact with acomplementary contact pin, the contact-making region comprising thefollowing features:

the contact-making region is essentially designed in the form of a boxwith two side walls, a top wall and a bottom wall,

the contact-making region has at least one contact spring arm, whichextends away from the conductor connection region;

the contact-making region has a supporting spring arm, which extendsaway from the conductor connection region and rests externally on thecontact spring arm.

U.S. Pat. No. 5,281,175 discloses an electrical female contact havingthe above features. The document relates to an electrical female,box-shaped contact with a resilient contact arm in the top wall with asupporting spring and a raised portion on the bottom wall. The contactis designed to receive different thicknesses of mating male terminals.It has a vertically extending tab for guidance in a housing. It isdesigned as a one part contact, may have an insertion funnel and isessentially rectangular in cross-section.

U.S. Pat. No. 3,836,947 also discloses a female electrical contact witha contact-making region with an essentially rectangular cross-section.One side of this region is in the form of a resilient leaf contactspring and a supporting spring overlying the contact spring.

DE 44 10 951 A1 concerns a flat spring contact, which has acontact-making region in the form of a box in which two contact springsare formed on one side wall, and a supporting spring, which rests on thesaid contact springs, is an independent part and is connected to thecontact-making region by fixing aids. Inwardly embossed contact pointsare provided on the side opposite to the contact springs.

U.S. Pat. No. Re 27,463 discloses a connector block for receiving andremovably holding an electrical contact in a cavity. The cavities arerectangular in cross-section. Female contacts having a conductorconnection region and a contact-making region are inserted into thecavities. The contact-making region of the contacts is essentiallybox-shaped and has the form of a trapezium in its cross-sectionperpendicular to the plug-in direction. The contacts and the connectorblock do not seem to have any polarising possibilities.

The object of the invention is to specify an electrical connector which,given a predetermined width of contact pins or blades and minimumcontact pin or blade spacings of a mating connector, neverthelesspermits reliable construction of robust chamber walls. In addition, itis intended to specify an electrical contact which is suitable for suchan electrical connector.

The object is achieved by means of a connector comprising a housing andat least one electrical contact, the housing having at least one chamberfor accommodating the electrical contact, the electrical contact havinga conductor connection region for connection to an electrical conductorwire and a contact-making region for making contact with a complementarycontact pin or blade, the contact-making region essentially beingdesigned in the form of a box with two side walls, a top wall and abottom wall, the bottom wall and the top wall having a different widthin the direction perpendicular to the plug-in direction, in such a waythat the side walls run in a manner inclined with respect to the bottomand top walls and with respect to one another, at least one chamberbeing trapezoidal in its cross-section.

Furthermore, the object of the invention is to specify an electricalcontact which permits contact to be made reliably with contact pins orblades whose thickness can be varied within specific tolerances.

The object is achieved by means of an electrical contact having aconductor connection region for connection to an electrical conductorwire and having a contact-making region for making contact with acomplementary contact pin, the contact-making region having thefollowing features:

the contact-making region is essentially designed in the form of a boxwith two side walls, a top wall and a bottom wall,

the contact-making region has at least one contact spring arm, whichextends away from the conductor connection region;

the contact-making region has a supporting spring arm, which extendsaway from the conductor connection region and rests externally on thecontact spring arm,

a compensating leaf spring being provided in the contact-making region,on the side opposite to the contact spring arm, and the bottom wall andthe top wall) having a different width in the direction perpendicular tothe plug-in direction, in such a way that the side wall run in a mannerinclined with respect to the bottom and top walls and with respect toone another.

Advantageous developments are specified in each of the subclaims.

As a result of the special design of the electrical contact, namely thetrapezoidal cross-section, it is possible to provide, between individualchambers which are designed to accommodate such a contact, chamber wallswhich are cross-sectionally wider on one side than on the other side. Asa result, it is possible to achieve, on the thin side, a minimal wallthickness which acquires the necessary robustness only by virtue of thefact that it is joined to a side wall and merges with a wider chamberwall on the other side.

It is particularly advantageous that the trapezoidal form at the sametime may be used as a polarising possibility. The advantage is achievedby providing in cross-section, trapezoidal contacts and chambers.

It is particularly advantageous that the electrical contact has acontact spring arm with a supporting spring, the spring properties ofthe contact spring being optimised thereby. Because of the trapezoidalform of the contact and the fact that the contact spring arm is arrangedin the broader top wall, the spring arm may be broad to achieve highcontact forces.

It is furthermore advantageous that a compensating leaf spring issituated on the side opposite to the contact spring. The springproperties of the contact spring arm and compensating leaf spring arecoordinated with one another in such a way that when a contact pin orcontact blade is introduced, initially it is mainly the contact springarm that is deflected. Only when the thickness of the contact pin orcontact blade exceeds a specific thickness the compensating leaf springis also deflected to a greater extent. The possible deflection of thecompensating leaf spring is advantageously limited by stops. Thecompensating leaf spring essentially serves to compensate for tolerancesin the thickness of the contact pin or contact blade. The compensatingleaf spring is substantially more rigid than the contact spring, whichhas a large elastic region, but less rigid than simple embossed areas orraised portions which are known from the prior art.

It is furthermore advantageous that an insertion funnel is formed at thefront end of the contact, which funnel serves to simplify the insertionof the contact pin or contact blade. This insertion funnel is formed bymeans of a lug which is bent back from the upper wall of thecontact-making region into the interior of the contact-making region.This upper lug can also serve as a stop if the contact spring arm isprestressed.

The conductor connection region can, for example, be designed as twodifferent crimp regions, one for crimping the conductor wire and one forcrimping the insulation of the conductor wire. However, it is alsopossible for the conductor connection region to have aninsulation-piercing terminal contact, or even to constitute acombination of insulation-piercing terminal contact and crimp contact.

It is particularly advantageous that the electrical contact describedcan be designed as a one-part contact. This enables particularlycost-effective production.

An exemplary embodiment of the invention is now explained with referenceto the drawings, in which:

FIG. 1 shows a plan view of an electrical contact;

FIG. 2 shows a side view of an electrical contact;

FIG. 3 shows a view of the front end of the electrical contact;

FIG. 4 shows a view from below of the electrical contact;

FIG. 5 shows a second side view of the electrical contact;

FIG. 6 shows a section through the conductor crimp;

FIG. 7 shows a section through the insulation crimp;

FIG. 8 shows a section along the section line BB according to FIG. 3;

FIG. 9 shows a section along the section line AA according to FIG. 8;

FIG. 10 shows a plan view of the layout of a contact which has beenstamped out but not yet folded;

FIG. 11 shows a longitudinal section through a slightly modifiedcontact;

FIG. 12 shows a layout of the slightly modified contact;

FIG. 13 shows a view of the plug-in face end of a housing;

FIG. 14 shows a section along the section line BB according to FIG. 13;

FIG. 15 shows a section along the section line AA according to FIG. 13;

FIG. 16 shows a view of a housing from the cable end;

FIG. 17 shows a section along the section line CC according to FIG. 13;and

FIG. 18 shows a detailed view of the detail X according to FIG. 15.

FIG. 1 illustrates a plan view of a contact 1 according to theinvention. The contact comprises a conductor connection region 2 and acontact-making region 3. The conductor connection region 2 serves forconnection to an electrical conductor 1 and has two crimp regions, aninsulation crimp 21 and a crimp for the electrical conductor wire 22.The contact-making region 3 serves to make contact with a complementarycontact pin, the contact pin being introduced into the contact-makingregion from the front end of the latter. As can be seen particularlyclearly in FIG. 2, which illustrates a view from the front end of thecontact, the contactmaking region is essentially designed in the form ofa box. This box is not rectangular but rather trapezoidal in itscross-section. As can be seen in FIG. 3, the contact-making region 3 hastwo side walls 4 and 5, a top wall 6 and a bottom wall 7. The bottomwall 7 is in this case designed to be narrower than the top wall 6,thereby achieving the trapezoidal appearance. The two side walls 4 and 5are therefore arranged such that they are inclined with respect to thetop wall and with respect to the bottom wall 7, and they also run in amanner inclined with respect to one another.

FIG. 1 permits a view of the top wall 6, it also being possible to seethe side walls 4 and 5. FIG. 2 shows a view of the side wall 5, and FIG.5 shows a view of the side arm wall 4. In both illustrations, thecontact spring arm 8 is illustrated by dashed lines. The contact springhas a free end at the front end of the electrical contact 1 and isconnected to the top wall 6 in the direction of the conductor connectionregion 2. As is evident from FIG. 2, the top wall comprises two layers61 and 62 in the region near to the conductor connection region 2. Thesupporting spring arm 9, which is both shown by dashed lines in theillustrations 2 and 5 and can also be seen in FIG. 1, is bent away fromthe upper layer 61. The said supporting spring supports the contactspring arm 8, which starts out from the lower layer 62 of the top wall6. Furthermore, the compensating leaf spring 10 can be seen in thefigures. This is a spring which is cut free at one end and extends awayfrom the conductor connection region. The spring is bent inwards, andtwo stops 11 and 12 start out from the bottom wall 7 and prevent thespring from overstretching. FIGS. 6 and 7 illustrate the sections alongthe section lines B and D through the two crimp regions. A lug 13extends forwards from the top wall 6 and is bent inwards into thecontact-making region 3. This lug serves as an insertion funnel for theinsertion of a complementary contact pin or contact blade.

FIG. 8 illustrates a section through the electrical contact 1 along thesection line BB according to FIG. 3. The top wall 6 with the two layers61 and 62 can be seen particularly clearly in this illustration. Thearrangement of contact spring arm 8 and supporting spring arm 9, as wellas compensating leaf spring 10 and stop 12, also becomes clear here. Inthe exemplary embodiment illustrated, the contact spring arm 8 is notprestressed, that is to say the lug 13 serves exclusively for forming aninsertion funnel. However, it is possible to achieve prestressing of thecontact spring arm 8. The lug 13 then likewise serves as a stop for theprestressed contact spring arm 8. The section illustrated also shows theopening 25, in which a latching means (illustrated by dashed lines) canengage in order to hold the contact in a chamber.

The cross-sectionally trapezoidal contact-making region can be seenclearly once again in FIG. 9, which illustrates a section along the lineAA through FIG. 8. The side walls 4 and 5 run in a manner inclined withrespect to one another. The compensating leaf spring 10 is situatedabove the stops 11 and 12 inside the contact-making region. The contactspring arm 8 is supported by the supporting spring arm 9. The contactspring arm 8 is bent in the contact-making region, as illustrated inFIG. 9. This bending extends over the entire length of the contactspring arm 8 in order to increase the stiffness.

The layout of the contact according to the invention can be seen clearlyin FIG. 10. The contact-making region 3 is formed by folding a number oftimes, the top wall being formed from two layers 61 and 62. The contactspring arm 8 is formed from the layer 61, while the supporting springarm 9 and the lug 13 are formed from the layer 62. The stops 11 and 12as well as the compensating leaf spring 10 are formed from the bottomwall 7. An opening 23 and a corresponding lug-24, which secures thelower layer of the wall 61 to the side wall, can be seen from thelayout. The cross-hatched regions on the contact spring arm 8 and thecompensating leaf spring 10 represent those regions of the contact whichare gold-plated for the purpose of better contact-making.

FIG. 11 illustrates a longitudinal section (as in FIG. 8) through afurther version of a contact and FIG. 12 illustrates a correspondinglayout. These differ from the contact illustrated in FIGS. 8 and 10 interms of the different compensating spring. The compensating leaf spring100 illustrated is joined at both ends and cut free only on the sides.Its deflection is thereby limited and stops are not provided.

FIGS. 13 to 18 then illustrate a housing which is suitable foraccommodating a contact according to the invention. The housing 14 hasfour contact chambers 17 to 20. The contact chambers each extend fromthe cable end of the housing 14 as far as the plug-in face end of thehousing, where openings are provided for the introduction ofcomplementary contact pins.

As emerges particularly clearly from FIG. 16, the view from the cableend of the housing, the chamber walls between the individual chambers 17to 20 are very thin. As a result of the inventive form of the contacts,namely their trapezoidal cross-section, it is possible for the width ofthe chamber walls to change over the layer thereof and, as a result, fora robust region to be produced at least on one side. This enables thecontacts, or the contact chambers, to be arranged as close to oneanother as possible.

From FIG. 15, it is evident that each contact chamber is assigned aflexible arm 15 having a latching lug 16 which engages in the contactchamber. When the contact is introduced, the latching lug 16 enters anopening 25 in the top wall 6 of the contact (see FIG. 1 or 8) andsecures the contact in the chamber.

The flexible arm 15 is illustrated once again, in detail, in FIG. 18. Itcan be seen here that the end face 26 of the flexible arm is bevelled.This bevelling serves the following purpose: if a contact is introducedincompletely into the contact chamber, the flexible contact arm 15 isbent outwards, that is to say out of the contact chamber. If an attemptis made in this state to connect a complementary connector to theillustrated connector, then a wall region of the complementaryconnector, which normally engages in the depression 27 (see FIG. 13),runs up against the oblique end face 26 of the flexible arm. The specialconfiguration of the end face prevents the flexible arm from beingpressed back into its original position by the wall region of thecomplementary connector even though the contact is incorrectlyintroduced. What is effected by this is that the flexible arm 15 ismoved even further out of the chamber.

What is claimed is:
 1. An electrical contact comprising a one piececonstruction having a conductor connection region for connection to anelectrical conductor and a contact-making region for making contact witha complementary contact, the contact-making region is formed as a box bytwo opposing side walls, a top wall and a bottom wall, where the topwall is wider than the bottom wall and the two opposing side walls areinclined with respect to each other and the top wall and the bottomwall, the contact making region having a contact spring arm extending atan inclination toward the bottom wall in a deflectable cantilevered formfrom the top wall, between the opposing side walls, and convergingtowards the bottom wall into a contacting region that would engage acomplementary contact when inserted into the contact-making region andthen diverging from the bottom wall to a free end, the contact springarm being wider where the arm emerges from the top wall than at thecontacting region and being tapered to fit between opposing side wallsconverging from the top wall toward the bottom wall, whereby highercontact forces would be generated upon the complementary contact than ifthe contact arm had a constant width equal to the contacting region. 2.The electrical contact of claim 1, wherein the top wall is of doublewall construction having a lower wall from which the contact arm extendsand an upper wall having a supporting spring arm that overlies thecontact arm.
 3. The electrical contact of claim 2, wherein the contactmaking region has an opening for receiving the complementary contactwhere the contact arm and supporting spring arm extend from the lowerwall and the upper wall respectively from locations closer to theconductor connection region than the opening and in a direction towardsthe opening.
 4. The electrical contact of claim 3, wherein the box ofthe contact-making region is of generally trapezoidal cross-sectionalconstruction.
 5. The electrical contact of claim 4, wherein the crosssection is symmetrical.
 6. The electrical contact of claim 5, wherein alug extends forward from the top wall and is bent back into the openingto define an insertion funnel.
 7. The electrical contact of claim 6,wherein the lug extends from the upper wall.
 8. The electrical contactof claim 1, wherein a compensating leaf spring extends into the contactmaking region from the bottom wall.
 9. The electrical contact of claim3, wherein a lug extends forward from the top wall and is bent back intothe opening and beneath the free end such that the free end of thecontact arm is located between the top wall and the lug.
 10. Theelectrical contact of claim 8, wherein the compensating leaf spring isjoined to the bottom wall at two ends thereof and free of the bottomwall along two sides thereof.
 11. The electrical contact of claim 8,wherein the compensating leaf spring extends in a cantilevered manneraway from the conductor connection region.
 12. The electrical contact ofclaim 11, wherein the free end of the contact arm rests freely betweenthe top wall and the lug.
 13. The electrical contact of claim 12,wherein the lug extends from the upper wall of the top wall.
 14. Anelectrical contact for use in an electrical connector including ahousing latch to secure the electrical contact in the electricalconnector, the electrical contact comprising a one piece box receptaclehaving a trapezoidal cross section, the box receptacle being formed byopposing side walls diverging upwardly for a bottom wall, and a top wallformed by upper and lower overlapping layers, with a cantilever contactspring arm extending from the lower layer toward the bottom wall, thelower layer being supported by one of the sidewalls behind thecantilevered contact spring arm, and a lug extending from a front edgeof the upper layer being folded downward and around to extend below aforward end of the cantilever contact spring arm in supportingrelationship to the cantilever contact spring arm.
 15. The electricalcontact of claim 14 wherein a supporting spring beam extends from theupper layer to engage the cantilever contact spring arm, both thecantilever contact spring arm and the supporting spring beam extendingbetween opposing sidewalls.
 16. The electrical contact of claim 14wherein the contact includes an opening in the top wall above thecantilever contact spring arm, the opening comprising means forreceiving a housing latch to secure the contact in the electricalconnector.
 17. The electrical contact of claim 14 wherein the cantilevercontact spring arm is preloaded or prestressed by the lug.
 18. Anelectrical contact for use in an electrical connector, the electricalcontact comprising a one piece box receptacle being formed by opposingside walls extending upwardly from the bottom wall, and a top wallformed by upper and lower overlapping layers, with a cantilever contactspring arm extending from the lower layer toward the bottom wall and acantilever supporting spring extending from the top layer, the lowerlayer being supported by one of the sidewalls behind the cantileveredcontact spring arm, and a lug extending from a front edge of the upperlayer being folded downward and around to extend below a forward end ofthe cantilever contact spring arm in supporting relationship to thecantilever contact spring arm so that the cantilever contact spring armis held between the lug and the cantilever supporting spring prior todeflection by a mating electrical contact.